Arm apparatus for mounting electronic devices

ABSTRACT

An extension arm suitable for mounting a flat-screen electronic peripheral device, including a forearm extension having at one end a first coupling for attachment to a tilter, a platform or other means for supporting a flat-screen device and at the other end a second coupling. The extension arm also includes a pair of end caps, each having a shaft. The shaft of the first end cap is pivotably rotatable in a support mount, such as a wall, desk or pole mount. The shaft of the second end cap is pivotably rotatable in the second coupling of the forearm extension. The extension arm also includes an upper channel and a lower channel. Each channel has at opposite ends a pair of integrally cast rollers which are pivotably attached to each of the end caps. The upper and lower channels and the end caps form an adjustable parallelogram.

REFERENCE TO CROSS-RELATED APPLICATIONS

[0001] The present application is a continuation of application Ser. No.09/405,628, filed Sep. 24, 1999, which claims the benefit of ApplicationNo. 60/133,378, filed on May 10, 1999, both entitled “Arm Apparatus forMounting Electronic Devices”, the disclosures of which are incorporatedherein.

BACKGROUND OF THE INVENTION

[0002] This invention relates to an arm apparatus for mountingelectronic devices and a method for manufacturing the arm apparatus, andmore specifically to an extension arm suitable to mount a flat-screenedelectronic peripheral device, such as a computer monitor or televisionand the method for manufacturing the extension arm.

[0003] Adjustable extension arms for mounting electronic peripheraldevices, such as a computer monitor or a television, are well known inthe prior art. However, due to recent advances in flat-screentechnology, there is a demand for adjustable extension arms that areparticularly suited for use with flat-screen devices, such as flatscreen computer monitors and televisions.

[0004] FIGS. 1-7 are assembly drawings of an extension arm 10 formounting a peripheral device, in accordance with the prior art. As shownin FIG. 1, the main elements of the extension arm 10 are a first end cap12, an upper channel 14, a lower channel 16, a second end cap 18, and aforearm extension 20. The first end cap 12 has an end cap shaft 22 thatis pivotably attachable to a rigid support mount (not shown), such as anorifice sized to accept the end cap shaft 22 or a track configured andsized to engage the grooves on end cap shaft 22. The first end cap 12 ispivotably coupled via pins 24 to both the upper channel 14 and the lowerchannel 16. The opposite ends of the upper channel 14 and the lowerchannel 16 are pivotably coupled via pins 24 to the second end cap 18.The second end cap 18 is coupled to the forearm extension 20 via aforearm extension pin 92. The forearm extension 20 has a verticallydisposed hole 26 therethrough for accepting a device mount (not shown)such as a tilter, platform or other apparatus. The combination of theupper and the lower channels 14, 16 and the first and the second endcaps 12, 18 form an adjustable parallelogram that permits a devicecoupled to the forearm extension 20 to be raised and lowered to adesirable height. The parallelogram retains its position by employing agas spring 28, which is pivotably and adjustably attached to the firstend cap 12 and the upper channel 14, as will be further described below.Generally, the gas spring 28 is sized so as to have a fixed length untilan upward or downward force is exerted at the second end cap 18 thatexceeds the gas spring's designed resistance. Thus, the gas spring 28causes the parallelogram to retain its position when the only forceexerted at the second end cap 18 is the weight of the device, butpermits the parallelogram to be adjusted when a user pushes the devicecoupled to the forearm extension 20 up or down.

[0005]FIG. 2 illustrates a side view of the first end cap 12, having theend cap shaft 22 disposed on a first end 30 of the first end cap 12. Toprovide a rigid connection between the two pieces, the end cap shaft 22is typically machined from steel and is inserted into the first end 30during the casting process of the first end cap 12. The end cap shaft 22has a hole 32 formed in an end of the end cap shaft 22 that is insertedinto the first end cap 12. The first end cap 12 is typically fabricatedfrom cast aluminum. The first end cap 12 also has a second end 34 havinga hole 36 disposed therethrough. Disposed within the first end cap 12 isa threaded rod 38. A first end 40 of the threaded rod 38 is insertedinto the hole 32 at the base of the end cap shaft 22. A second end 42 ofthe threaded rod 38 is aligned with the hole 36 and is held in place bya clip 44. The clip 44 is fastened to an inner surface of the first endcap 12 by screws 46.

[0006] Threadedly mounted on the threaded rod 38 is a clevis 48. FIG. 3illustrates a sideview of the clevis 48 including a tapped hole 50 inthe center thereof. The tapped hole 50 receives the threaded rod 38, asshown in FIG. 2. At a first end of the clevis 48 is a pair of fasteningmembers 52, 54 to which are fastened one end of the gas spring 28. Asecond end 56 of the clevis 48 is configured to slidably engage a track58 which is integrally molded in the first end cap 12 (see FIG. 2). Thesecond end 42 of the threaded rod 38 is configured to be engaged by ahex-shaped key which is inserted through the hole 36 when the second end42 is properly aligned with the hole 36. The hex-shaped key is employedso as to rotate the threaded rod 38 along its axis of rotation. When thethreaded rod 38 is rotated along its axis of rotation, the clevis 48moves along the length of the threaded rod 38 in a direction thatcorresponds to the direction which the hex-shaped key is turned. Thismovement of the clevis 48 permits the gas spring 28 to be adjusted.

[0007] FIGS. 4(a) and 4(b) illustrate the upper channel 14, whichcomprises channel bottom 60 from which extend two channel sidewalls 62.Channel bottom 60 and sidewalls 62 are typically stamped from 13 gaugesteel sheet in order to give the upper channel 14 a desired degree ofstructural rigidity. At each of the ends of the channel bottom 60, asemi-circular region 64 of the sidewalls 62 is cut out to accommodatecold-rolled steel rollers 66, which have a hole 68 therethrough forreceiving the pins 24. The rollers 66 are rigidly attached to the upperchannel 14 by MIG welding along the edge of the semi-circular cut outregion 64 and along the ends of the channel bottom 60.

[0008] Additionally, the upper channel 14 comprises stiffener 70, whichis welded to an inner surface of the channel bottom 60. Besidesproviding additional structural rigidity to the upper channel 14, thestiffener 70 has a hole disposed at one end with a threaded ball stud 72placed within the hole and fixed in place by a nut 74. The ball stud 72is configured and sized to receive one end of the gas spring 28. Thelongitudinal centerline 76 of the upper channel 14 is illustrated inFIG. 4(b).

[0009] FIGS. 5(a) and 5(b) illustrate the lower channel 16 whichcomprises a channel bottom 78 from which extend two channel sidewalls80. As with the upper channel 14, the channel bottom 78 and sidewalls 80are typically stamped from 13 gauge steel sheet, which is relativelyheavy in order to give the lower channel 16 a desired degree ofstructural rigidity. At opposite ends of the channel bottom 78, asemicircular region 82 of the sidewalls 80 is cut out to accommodatecold-rolled steel rollers 84, which have a hole 86 therethrough forreceiving the pins 24. The rollers 84 are rigidly attached to the lowerchannel 16 by MIG welding along the edge of the semi-circular cut outregion 82 and along the ends of the channel bottom 78. The longitudinalcenterline 88 of the lower channel 16 is illustrated on FIG. 5(b)

[0010]FIG. 6 illustrates the second end cap 18. Unlike the first end cap12, the second end cap 18 does not have an end cap shaft, nor does ithave a clevis assembly for attachment to the gas spring 28. Instead, thesecond end cap 18 has a hole 90 disposed in a bottom end for receivingthe forearm extension pin 92, and a hole 94 in a side for inserting apin 96 into the forearm extension pin 92, as illustrated in FIG. 1.

[0011]FIG. 7 illustrates the forearm extension 20 having the forearmextension pin 92 welded thereto. The forearm extension pin 92 has a hole98 formed in an upper end to receive the pin 96. The forearm extension20 is configured to be pivoted around the forearm extension pin 92, andis held in place within the second end cap 18 by the pin 96 whichpenetrates the hole 94 of the second end cap 18 and the hole 98 of theforearm extension pin 92.

[0012] Extension arms 10 of the prior art, such as the one shown inFIGS. 1-7 and others like it, are ill-suited for flat-screen monitorsand televisions, in that they are bulky and cumbersome. In addition, dueto the configuration of its various parts, extension arms 10 of theprior art cannot be flattened against a mounting surface so that theentire extension arm 10 is hidden behind the flat screen device when thedevice is substantially flush with the mounting surface. Additionally,the extension arms 10 of the prior art are costly to manufacture anddifficult to assemble.

[0013] Thus, there is a need for an extension arm suitable to mount aflat-screened electronic peripheral device, such as a computer monitoror television, that is inexpensive and easy to manufacture and assemble,and that permits a flat-screen device to be mounted substantially flushwith the mounting surface.

SUMMARY OF THE INVENTION

[0014] The present invention, in accordance with one embodiment, relatesto an extension arm suitable for mounting a flat-screened electronicperipheral device, such as a computer monitor or television. Theextension arm is inexpensive and easy to manufacture and assemble, andpermits a flat-screen device to be mounted substantially flush with amounting surface.

[0015] According to one embodiment, the extension arm comprises aforearm extension that has at one end a first coupling for attachment toa tilter, a platform or other means for supporting a flat-screen device.At the other end of the forearm extension is a second coupling. Theextension arm also comprises a pair of end caps each having an end capshaft. The end cap shaft of the first end cap is pivotably rotatable ina support mount, such as a wall, desk or pole mount. The end cap shaftof the second end cap is pivotable rotatable in the second coupling ofthe forearm extension.

[0016] The extension arm also comprises an upper channel and a lowerchannel. The upper channel has at opposite ends a pair of integrallycast rollers. Each roller is pivotably attached to each of the end caps.The lower channel also has at opposite ends a pair of integrally castrollers, which are pivotably attached to each end cap. The upper andlower channels and the end caps form an adjustable parallelogram. Theshape of the parallelogram is retained by a gas spring. One end of thegas spring is attached to a ball stud mounted in the upper channel. Theother end of the gas spring is adjustably mounted to the first end cap.

[0017] The extension arm also comprises a clevis, which is locatedwithin the first end cap. The clevis is pivotably attached to the end ofthe gas spring which is mounted in the first end cap. A threaded rodthreadedly engages the clevis, such that the clevis slides within thefirst end cap when the rod rotates around its axial centerline. Thethreaded rod is rotatably secured within the first end cap by a retainerclip and a pair of screws.

[0018] In one embodiment of the present invention, an upper channel foruse in an extension arm that adjustably mounts a device to a supportmount, the upper channel comprising a U-shaped body having first andsecond ends, the body including a pair of spaced apart sidewalls and abottom wall, a first roller at a first end of the body and a secondroller at a second end of the body, the first roller including a pair ofspaced apart roller walls extending between the sidewalls from thebottom wall, the height of the roller walls from the bottom wall beingless than the height of another portion of the first roller from thebottom wall.

[0019] In another embodiment of the present invention, a lower channelfor use in an extension arm that adjustably mounts a device to a supportmount, the lower channel comprising a U-shaped body having first andsecond ends, the body including a pair of spaced apart sidewalls and abottom wall, a first roller at a first end of the body and a secondroller at a second end of the body, the first roller including a pair ofspaced apart roller walls extending between the sidewalls from thebottom wall, the height of the roller walls from the bottom wall beingless than the height of the remaining portion of the first roller fromthe bottom wall.

[0020] In another embodiment of the present invention, the combinationof an upper channel and a lower channel for use in an extension arm thatadjustably mounts a device to a supporting mount, the combinationcomprising an upper channel including a U-shaped upper body having firstand second ends, the upper body including a pair of spaced apartsidewalls and a bottom wall, a first roller at a first end of the upperbody and a second roller at a second end of the upper body, the firstroller including a pair of spaced apart roller walls extending betweenthe sidewalls from the bottom wall, the height of the roller walls fromthe bottom wall being less than the height of the remaining portion ofthe first roller from the bottom wall; and a lower channel including aU-shaped lower body having first and second ends, the lower bodyincluding a pair of spaced apart sidewalls and a bottom wall, a thirdroller at a first end of the lower body and a fourth roller at a secondend of the body, the third roller including a pair of spaced apartroller walls extending between the sidewalls from the bottom wall, theheight of the roller walls from the bottom wall being less to the heightof the remaining portion of the third roller from the bottom wall,wherein the upper and lower body and the respective rollers areintegrally cast.

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The subject matter regarded as the invention is particularlypointed out and distinctly claimed in the concluding portion of thespecification. The invention, however, both as to organization andmethod of operation, together with features, objects, and advantagesthereof may best be understood by reference to the following detaileddescription when read with the accompanying drawings in which:

[0022]FIG. 1 is an assembly drawing of an extension arm for mounting acomputer monitor, in accordance with the prior art;

[0023]FIG. 2 illustrates a first end cap of an extension arm, inaccordance with the prior art;

[0024]FIG. 3 illustrates the clevis assembly of an extension arm, inaccordance with the prior art;

[0025] FIGS. 4(a) and 4(b) illustrate the upper channel of an extensionarm, in accordance with the prior art;

[0026] FIGS. 5(a) and 5(b) illustrate the lower channel of an extensionarm, in accordance with the prior art;

[0027]FIG. 6 illustrates a second end cap of an extension arm, inaccordance with the prior art;

[0028]FIG. 7 illustrates a forearm extension of an extension arm, inaccordance with the prior art;

[0029]FIG. 8 is an exploded assembly drawing of an extension arm foradjustably mounting a flat-screen device to a support mount, accordingto one embodiment of the invention;

[0030] FIGS. 9(a)-(d) show several views of end caps, in accordance withone embodiment of the invention;

[0031] FIGS. 10(a)-(d) illustrate several views of an upper channel,according to one embodiment of the invention;

[0032] FIGS. 11(a)-(e) illustrate several views of a lower channel,according to one embodiment of the invention;

[0033] FIGS. 12(a) and 12(b) illustrate a forearm extension, inaccordance with one embodiment of the invention; and

[0034] FIGS. 13(a) and 13(b) illustrate a forearm extension, inaccordance with one embodiment of the invention.

DETAILED DESCRIPTION

[0035] The present invention, in accordance with one embodiment, relatesto an extension arm suitable for mounting a flat-screen electronicperipheral device, such as a computer monitor or television, and themethod of manufacturing the extension arm. FIG. 8 is an explodedassembly drawing of the extension arm, for adjustably mounting a deviceto a support mount, according to one embodiment of the invention.

[0036] In the embodiment shown, the extension arm 100 comprises a firstend cap 102, an upper channel 104, a lower channel 106, a second end cap108, and a forearm extension 110. The first end cap 102 and the secondend cap 108 both include a partially enclosed housing 112 and a shaft114. The partially enclosed housing 112 of both the first and the secondend caps 102, 108 is configured with, for example, holes 116 to receivea connection mechanism, such as a pin 118, therethrough. The shaft 114of the first end cap 102 is configured to be inserted for pivotablerotation in a support mount (not shown), which may be a wall, a desk, apole mount, or a configurable mount as shown and described inApplicant's co-pending patent applications: application No. 60/106,729filed on Nov. 2, 1998 and application No. 60/108,469 filed on Nov. 14,1998. The shaft 114 of the second end cap 108 is configured to beinserted for pivotable rotation in the forearm extension 110.

[0037] The partially enclosed housing 112 of the first end cap 102 alsoincludes a clevis 120, which is pivotably attached to an end of a gasspring 122, mounted therein. A threaded rod 124 is in threadedengagement with the clevis 120, such that the clevis 120 is configuredto slide within the first end cap 102 when the threaded rod 124 rotateson its axis. The threaded rod 124 is rotatably secured in the first endcap 102 by a retainer clip 126 that is attached to the first end cap 102with, for example, screws 128.

[0038] The upper channel 104 includes a U-shaped body 130 and integrallycast rollers 132 disposed at opposite ends of the U-shaped body 130.Each of the rollers 132 is configured to be pivotably attached to arespective one of the first end cap 102 and the second end cap 108 with,for example, the pins 118. The lower channel 106 also includes aU-shaped body 134 and integrally cast rollers 136 disposed at oppositeends of the U-shaped body 134. Each of the rollers 136 is configured tobe pivotably attached to a respective one of the first end cap 102 andthe second end cap 108 with, for example, the pins 118.

[0039] The upper and the lower channels 104, 106 and the first and thesecond end caps 102, 108 are configured so as to form an adjustableparallelogram. When configured, the shaft 114 of the first end cap 102and the shaft 114 of the second end cap 108 point in oppositedirections. For example, the shaft 114 of the first end cap 102 extendsvertically downward while the shaft 114 of the second end cap 108extends vertically upward. The shape of the parallelogram is retained bythe gas spring 122. One end of the gas spring 122 is attached to a ballstud 138 which is mounted to the upper channel 104. The other end of thegas spring 122 is adjustably mounted to the clevis 120 within the firstend cap 102. Generally, the gas spring 122 is sized so as to have afixed length until an upward or downward force is exerted at the secondend cap 108 that exceeds the gas spring's designed resistance. Thus, thegas spring 122 retains the parallelogram shape when the only forceexerted at the second end cap 108 is the weight of the flat-screendevice. However, the gas spring 122 permits the parallelogram shape tobe adjusted when a user pushes the flat-screen device coupled to theforearm extension 110 up or down.

[0040] The forearm extension 110 includes a body 140 having a firstfemale coupling 142 located on a first end and a second female coupling144 located on a second end. The first female coupling 142 is forattachment to the shaft 114 of the second end cap 108. The second femalecoupling 144 is for attachment to a device mounting (not shown) such asa tilter, as described in Applicant's co-pending patent application No.60/137,088 filed on Jun. 2, 1999; a platform or other means forsupporting a flat-screen device.

[0041] Additional advantages and features of the individual components,according to various embodiments of the present invention, are furtherdescribed below.

[0042] End Caps 102, 108

[0043]FIG. 9(a) illustrates a side view, and FIG. 9(b) illustrates a topview of the first end cap 102 and the second end cap 108, in accordancewith one embodiment of the invention. In the embodiment shown, each ofthe first and second end caps 102, 108 includes the partially-enclosedhousing 112 which has flat, oppositely-disposed endwalls 146 and 148fixedly connected by a sidewall 150. The sidewall 150 extends partiallyaround the partially-enclosed housing 112 so as to permit manipulationof components to be assembled within the first and second end caps 102,108. In one embodiment, the endwalls 146 and 148 are semicircular inshape and are connected along a semi-circular edge to the sidewall 150,which extends perpendicularly therebetween.

[0044]FIG. 9(a) is a side view (from the perspective of the open regionof the sidewall 150), that illustrates the first and the second end caps102, 108 having the shaft 114 disposed on the endwall 148. The shaft 114is preferably integrally molded to the endwall 148 of each of the endcaps 102, 108. Preferably the entire end caps 102, 108 (partiallyenclosed housings 112 and shafts 114) are molded from zinc. The endwall146 has a hole 152 disposed therethrough. Within the partially enclosedhousing 112 and integrally molded on the sidewall 150 adjacent theendwalls 146, 148 are stops 156. The stops 156 serve to stop upward ordownward movement of the extension arm 100 when ends of the lowerchannel 106 and the upper channel 104, respectively, meet the stops 156when the extension arm 100 is in extended positions.

[0045] Also within the partially-enclosed housing 112, and integrallymolded to the inner surface of the sidewall 150 are trough walls 158which run longitudinally along the inner surface of the sidewall 150between the endwalls 146 and 148 so as to define a trough 160therebetween. FIG. 9(b) illustrates a side view of the trough 160disposed between the trough walls 158.

[0046] Additionally within the partially enclosed housing 112 andintegrally molded with the inner surface of the sidewall 150, andproximate the endwall 148, are shelves 162. FIG. 9(b) illustrates a sideview of the shelves 162 which define co-planar faces separated by agroove 164. The shelves 162 have a connection means, such asself-tapping screw holes 154 disposed therein. The co-planar faces ofthe shelves 162 are configured to engage the retainer clip 126, which isfastened in place by, for example, the pair of screws 128. When theretainer clip 126 is fastened in place, the groove 164 defines a spacingfor accepting one end of the threaded rod 124, as discussed below.

[0047] The first end cap 102 and the second end cap 108 are identical atthis point. However, while the manufacturing of the second end cap 108is complete, the first end cap 102 still requires assembly of thethreaded rod 124 and the clevis 120. The threaded rod 124 is employedwithin the first end cap 102 so as to adjustably support the clevis 120.FIG. 9(c) illustrates the threaded rod 124 in greater detail. A firstend 166 has a circular cross-section within which is axially disposed ashaped opening 168, for example a hex-shaped opening, for accepting ashaped key (not shown), such as a hex-shaped key. Advantageously, across-sectional diameter of the first end 166 is smaller than across-sectional diameter of the hole 152, so as to be inserted therein.Adjacent the first end 166 is a shoulder 170. Advantageously, theshoulder 170 has a circular cross-section having a diameter that islarger than the cross-sectional diameter of the hole 152. Thus, in thepreferred embodiment, the shoulder 170 abuts an inner surface of theendwall 146 and retains the first end 166 within the hole 152.

[0048] The threaded rod 124 also includes a threaded section 172 whichis configured to threadingly engage the clevis 120. The second end 174of the threaded rod 124 is disposed in the groove 164 located betweenthe shelves 162 of the first end cap 102. Preferably, the second end 174of the threaded rod 124 has a circular cross-section having a diameterthat is smaller than the size of the groove 164, such that the secondend 174 is supported between the shelves 162 but is free to rotatetherein.

[0049] As previously mentioned, threadedly mounted on the threaded rod124 is the clevis 120. The clevis 120 as illustrated in FIG. 9(d), has atapped hole 176 formed therein for receiving the threaded rod 124. Theclevis 120 also has a fastening member 178 at a first end, which isfastened to one end of the gas spring 122. The second end of the clevis120 is configured to slidably engage the trough 160.

[0050] When the first end 166 of the threaded rod 124 is engaged by theshaped key, the shaped key is employed so as to rotate the threaded rod124 around its axial centerline. When the threaded rod 124 is rotatedaround this axis of rotation, the clevis 120 moves along the length ofthe threaded rod 124 in a direction that corresponds to the directionwhich the hex-shaped key is turned. This movement of the clevis 120permits the gas spring 122 to be adjusted.

[0051] The end caps 102, 108 have numerous manufacturing advantages overthe end caps 12, 18 of the prior art, and others like it. Unlike theprior art end caps 12, 18 which are different from each other, the endcaps 102, 108 are advantageously manufactured the same way. The threadedrod assembly 124 and the clevis 120 of the first end cap 102 aresubsequently assembled in the first end cap 102. Thus, the cost ofmanufacturing two different kinds of end caps are eliminated.

[0052] Moreover, the cost of manufacturing each end cap 102, 108 isreduced significantly. In the prior art, a significant part of the costof the first end cap 12 is the steel shaft 22, which is machinedseparately, and then is inserted into the aluminum cast mold. Bycontrast, the shaft 114 is integrally molded with the end caps 102, 108by employing interlocking mold technology. Interlocking molds permit anear-perfect mold to be made, minimizing the˜machining that is requiredto insure that the shaft 114 is not out-of-round. By minimizing theamount of machining that is required to be performed on the shaft 114,the use of interlocking molds insures that the strength of the casting,which is primarily located in the skin of the cast, is maximized.

[0053] As previously mentioned, all the components of the endcaps 102,108 are preferably cast molded from zinc, though the present inventionis not limited in scope in this respect. Using zinc for the partiallyenclosed housings 112 is an improvement over the aluminum end caps 12,18 employed in the prior art. That is, the zinc is stronger and moreflexible than the aluminum.

[0054] The first end cap 102 also has numerous assembly advantages overthe first end cap 12 of the prior art, and others like it. For instance,the assembly time required to rotatably fasten the threaded rod 124 inthe first end cap 102 is greatly reduced. In order to assemble thethreaded rod 124 of the present invention, the first end 166 is insertedinto the hole 152 until the shoulder 170 abuts the inner surface of theendwall 146. The second end 174 of the threaded rod 124 is thenpositioned in the groove 164 between the shelves 162. The second end 174is held in place by the retainer clip 126 which is fastened in place by,for example, the screws 128, which are easily accessible due to theirproximity above the threaded rod 124. The first end 166 of the threadedrod 124 is perfectly aligned with the hole 152, and will remain so,because it is inserted for rotation therein.

[0055] By contrast, the assembly of the threaded rod 38 in the first endcap 12 of the prior art is more complicated, and therefore, more costly.For example, the first end 40 is inserted into the hole 32 in the baseof the end cap shaft 22. Next, the clevis 48 is mounted on the rod 38,and then the second end 42 is fastened inside the first end cap 12 bythe clip 44. The clip 44 is also employed to align the second end 42relative to the hole 36. Thus, the clip 44 must be fastened inside thefirst end cap 12 with precision, so as to insure that the second end 42is aligned relative to the hole 36 such that the second end 42 can beengaged by a hex-shaped key which is inserted into the hole 36.Moreover, the screws 46 which are employed to the fasten clip 44 insidethe first end cap 12 are difficult to access due to their positionunderneath the rod 38, thus complicating the process of aligning thesecond end 42 with the hole 36. In addition, the fastening of the clip44 inside the first end cap 12 is also rendered more difficult becausethe clevis 48 is already attached to the gas spring 28.

[0056] Unlike the prior art, the current invention does not require aforearm extension pin 92 to connect the second end cap 18 to the forearmextension 20. Moreover, the pin 96 is not required to hold the forearmextension pin 92 within the second end cap 18. Instead, the currentinvention uses the shaft 114 of the second end cap 108 to connect thesecond end cap 108 to the forearm extension 110. Thus, manufacturingcosts can be reduced since there in no need to manufacture the forearmextension pin 92 or the pin 96, and there is no reason to form the hole94 within the second end cap 18 or the hole 98 within the forearmextension pin 92 to accept the pin 96.

[0057] Upper Channel 104

[0058]FIGS. 10a-d illustrate several views of the upper channel 104,according to one embodiment of the invention. The U-shaped body 130 ofthe upper channel 104 comprises a channel bottom 180 from which extendtwo channel sidewalls 182. Unlike the upper channel 14 of the prior artextension arm shown in FIGS. 4a-b, which is stamped from heavy gaugesteel, the channel bottom 180 and the sidewall-S 182 of the upperchannel 104 are preferably integrally cast from zinc, which gives theupper channel 104 a lesser weight, and a degree of structural rigidity,more suitable for lighter-weight flat screen devices. At each end of thechannel bottom 180 are the rollers 132, which are also integrally cast.The rollers 132 have a hole 184 therethrough (either cast orsubsequently drilled) for receiving a connection mechanism, such as thepins 118. Additionally, the upper channel 104 comprises a threaded hole186 configured and sized to receive a threaded end of the ball stud 138.The threaded hole 186 is also integrally cast. The ball stud 138 isconfigured and sized to receive one end of the gas spring 122.

[0059] The upper channel 104 has numerous manufacturing advantages overthe upper channel 14 of the prior art, and others like it. For instance,with reference to the upper channel 14 of the prior art shown in FIGS.4a-b, the welding which is required to attach the rollers 66 to theupper channel 14 is difficult to perform. The axial centerlines of therollers 66 must be near-perfectly parallel to each other, while beingnear-perfectly perpendicular to the longitudinal centerline 76 of thechannel bottom 60. The tolerances for these angles are very small so asto insure that the lower channel 16 engages the upper channel 14 whenthe parallelogram is adjusted. These tolerances are very difficult tomeet when the rollers 66 are welded to the upper channel 14. Bycontrast, the rollers 132 of the upper channel 104 of the presentinvention are integrally cast so as to insure that the axial centerlinesof rollers 132 are simultaneously perfectly parallel to each other andperfectly perpendicular to a longitudinal centerline 188 of the channelbottom 180.

[0060] Additionally, with further reference to FIGS. 4a-b and aspreviously noted, due to the hardness of the steel employed for theprior art upper channel 14, the rollers 66 must be MIG welded thereto,which in turn requires the rollers 66 to be fabricated from expensivecold-rolled steel. Although it is tempting for a manufacturer of therollers 66 to employ a cheaper material, such as leadloy, these cheapermaterials do not provide a safe and consistent weld when joined to thesteel upper channel 14. Typically, tests must be performed on the rollermaterial to insure that leadloy has not been supplied. By contrast, theupper channel 104 of the present invention requires no welding,eliminating the cost of aligning the rollers, the cost of performing thewelding and the cost of testing the rollers to determine if they are asuitable welding material.

[0061] In additional disadvantage of welding the rollers 66 to the upperchannel 14 is that the heat produced by welding the rollers 66 to theupper channel 14 may cause the upper channel 14 to curl or deform. Ifthis occurs, alignment of the rollers 66 is ruined and the upper channel14 is rendered useless, requiring it to be discarded. By eliminating anywelding required during the manufacture of the upper channel 104, thelikelihood of heat-deforming the upper channel 2-04 is also eliminatedand materials are not wasted.

[0062] As previously mentioned, the prior art upper channel 14 is madeof steel, which means that the upper channel 14 is formed by heating apiece of steel and bending the steel to form the channel bottom 60 aridthe sidewalls 62. Thus, precise manufacturing is required to ensure thesidewalls 62 extend up from the channel bottom 60 at 90 degree angles.If the angle is slightly off it will likely cause the upper channel 14and the lower channel 16 to scrape against one another. The use of castmolding in the current invention ensures the angle between the channelbottom 180 and the sidewalls 182 is exactly the same each and everytime. Thus, the likelihood of scraping is greatly reduced, if noteliminated.

[0063] Moreover, as illustrated in FIGS. 10c and 10 d, which arecross-sectional views of the upper channel 104, the sidewalls 182 aretapered. Both an outer surface and an inner surface of the sidewalls 180tapers in approximately 1 degree. The taper is possible because theupper channel 104 is, in the preferred embodiment, cast molded. Thetaper provides several advantages including more clearance between theupper and the lower channels 104, 106 when the upper and the lowerchannels 104, 106 are brought together during usage. That is, the innersurface of the sidewall 180 being displaced by 1 degree means that therewill be additional clearance for the lower channel 106 to fittherewithin. The additional clearance will help prevent the upperchannel 104 and the lower channel 106 from scraping together. Thus,damage to the paint or other coating that may cover the upper and thelower channels 104, 106 will be further reduced, if not eliminated.Moreover, less material is needed at outer edges of the sidewalls 182.Furthermore, the taper is more aesthetically pleasing to the eye of theuser.

[0064] Additionally, the upper channel 104 eliminates the requirementfor the stiffener 70, which, with reference to FIGS. 4a-b, is welded tothe inner surface of the channel bottom 60 in the upper channel 14 ofthe prior art. Unlike the upper channel 14 of the prior art, the upperchannel 104 does not require the additional structural rigidity providedby the stiffener 70. By eliminating the stiffener 70, the upper channel104 of the present invention also saves the steps required to weld thestiffener 70 to the channel bottom 60 which are required by the priorart upper channel 14.

[0065] Moreover, additional assembly steps are saved by integrallycasting the threaded hole 186 in the upper channel 104 of the currentinvention. For instance, the prior art upper channel 14 has the threadedball stud 72 penetrate a hole disposed in the stiffener 70 and is fixedin place by the nut 74. In order to install the bail˜1 stud 72, it isrequired that the threaded end of ball, stud 72 be inserted through thehole in the stiffener 70 and be fixed in place by the nut 74 prior tothe stiffener 70 being welded in place. No such assembly is requiredwith the upper channel 104 of the present invention.

[0066] An additional problem experienced by prior art upper channels 14is the need to mask openings, such as the holes 68 in the rollers 66that receive the pins 28 therethrough, when the upper channel is paintedor otherwise coated. Specifically, labor is required in order to insertmasking material into the openings and then to remove the maskingmaterial after the paint has been applied. By contrast, the openings ofthe present invention are according to one embodiment, precision-drilledafter an application of paint or other coatings, thus eliminating theexpense of masking any openings.

[0067] Lower Channel 106

[0068]FIGS. 11a-e illustrate several views of the lower channel 106,according to one embodiment of the invention. The U-shaped body 134 ofthe lower channel 106 comprises a channel bottom 190 from which extendtwo channel side walls 192. Unlike the lower channel 16 of the prior artextension arm shown in FIGS. 5a-b, which is stamped from heavy gaugesteel, the channel bottom 190 and sidewalls 192 of the lower channel 106are preferably integrally cast from zinc, which gives the lower channel106 a lesser weight when compared to heavy gauge steel, and a degree ofstructural rigidity, more suitable for lighter-weight flat screendevices. At each end of the channel bottom 180 are the rollers 136,which are also integrally cast. The rollers 136 have a hole 194therethrough (either cast or subsequently drilled) for receiving aconnection mechanism, such as the pins 118. The channel bottom 190additionally includes a cable channel aperture 196 runninglongitudinally. In the embodiment shown, the cable channel aperture 196has rounded ends, which improves the rigidity of the lower channel 106.The cable channel aperture 196 is configured to receive a cable cover198 (illustrated in Fig. lie). The cable cover 198 is configured toremovably fit within the cable channel aperture 196. Thus, cables of themounted device may be substantially retained within the lower channel106 so as to hide them from view and protect them from harm. The cablechannel aperture 196 and the cable cover 198 enable cables to beaccessed when desired, while securing them within the lower channel 106.

[0069] The lower channel 106 has numerous manufacturing advantages overthe lower channel 16 of the prior art, and other like it. For instance,as described above with reference to the upper channel 104, the rollers136 of the lower channel 106 of the present invention are integrallycast so as to insure that the axial centerlines of the rollers 136 areperfectly parallel to each other, and that the axial centerlines of therollers 136 are perfectly perpendicular to a longitudinal centerline 200of the channel bottom 2-90. Thus, the need for precision alignment ofthe rollers 84 prior to welding to the lower channel 16 is eliminated.

[0070] Additionally, and as also described with reference to the upperchannel 104, the rollers 136 of the lower channel 106 are integrallycast so no welding is required. Thus, the cost of performing the weldingand the cost of testing the rollers to determine if they are a suitablewelding material is eliminated. Another advantage of eliminating theneed for welding the rollers 136 to the lower channel 106 is reducingthe likelihood of heat-deforming the lower channel 106 so that materialsare not wasted.

[0071] As shown in FIGS. 11c and 11 d, which are cross-sectional viewsof the lower channel 106, the sidewalls 192 of the lower channel 106 aretapered. An outer surface of the sidewalls 192 is tappered approximately½ degree while an inner surface is tappered approximately 1 degree. Thetaper is possible because the lower channel 106 is, in the preferredembodiment, cast molded. As rioted above with respect to the upperchannel 104, the taper provides more clearance between the upper channel104 and the lower channel 106 so as to reduce or eliminate the chance ofthe upper and the lower channels 104, 106 scraping. Moreover, lessmaterial is needed at outer edges of the sidewalls 192. A furtheradvantage, as noted above with respect to the upper channel 104, is thatthe hole 194 within the rollers 136, according to one embodiment, isprecision-drilled after an application of paint or other coatings, thuseliminating the expense of masking any openings.

[0072] As illustrated in FIG. 11e, the cable cover 198 includes a topcover 202 with two sidewalls 204 pertruding therefrom. A far end of eachsidewall 204 has a catch 206 formed thereon so as to engage with thecable channel aperature 196.

[0073] Forearm Extension 110

[0074] With reference to FIGS. 12a, 12 b, 13 a and 13 b, the forearmextension 110 includes a body 140, which is preferably U-shaped so thata cable can be hidden therein, having female couplings 142, 144 disposedat each end. The V-shaped body 140 includes a topwall 207 and two sidewalls 208. The female coupling 142 has an inner diameter 209 that issized to rotatably engage the shaft 114 of the second end cap 108. Asillustrated in FIG. 8, the forearm extension 110 and the shaft 114 aresecurely fastened to each other by connecting a screw 211 through acoupling top 213 into a hole 215 (FIG. 9a) within the shaft 114.

[0075] A bushing 210 (FIG. 8) is preferably used to engage the femalecoupling 142 and the shaft 114. That is, the bushing 210 is placed overthe shaft 114 and within the female coupling 142. The bushing 210 ispreferably made of a smooth material, such as plastic, in order toreduce friction and prevent metal to metal contact. The female coupling142 preferably has a set screw 212 formed within a wall 214 of thefemale coupling 142. The set screw 212 is aligned to press against thebushing 210 at approximately the location of a ridge 216 (see FIG. 9a)on the shaft 114 of the second end cap 108. When the set screw 212 istightened it causes the bushing 210 to flex inward and frictionallyengage the shaft 114 and thus prevent the forearm extension 110 fromrotating about the shaft 114. Advantageously, the female coupling 142has a plurality of voids 217 formed in the wall 214, which saves onmaterial costs and permits the forearm extension 210, when cast, to becooled more quickly. The quicker cooling enables the production quantityto be increased.

[0076] The female coupling 144 has an inner diameter 218 that is sizedto rotatably engage a shaft of a device mount, such as a tilter,platform or other device used to secure flat-screen devices. A bushing220 (FIG. 8), preferably made of a smooth material such as plastic, isplaced over the shaft and within the female coupling 144. The femalecoupling 144 preferably has a set screw 222 formed within a wall 224 ofthe female coupling 144. When the set screw 222 is tightened it. causesthe bushing 220 to flex inward and frictionally engage the shaft andthus prevent the device mount from rotating around the female coupling144. Advantageously, the female coupling 144 also has a plurality ofvoids 226 formed in the wall 224.

[0077]FIGS. 12a and 2˜2 b illustrate one embodiment of the forearmextension 110, wherein the center of the female couplings 142, 144 arealigned with a longitudinal centerline 228 of the body 140. Asillustrated in FIG. 12b, when the axial centerlines of the femalecouplings 142, 144 are vertically disposed, the body 140 inclines at anangle, such as a 15 degree angle as specifically illustrated in FIG.12b. It should be noted however that the incline angle is not limited to15 degrees, and there may in fact be no incline at all in thisembodiment.

[0078]FIGS. 13a and 13 b illustrate another embodiment of the forearmextension 110, wherein the center of the female couplings 142, 144 donot align with the axial centerline 228 of the body 140. Rather the body140 is flush with an upper edge of the female coupling 142, resulting inthe center of the female coupling 142 being offset from the center ofthe female coupling 144. As illustrated in FIG. 13b, when the axialcenterlines of the female couplings 142, 144 are vertically disposed,the body 140 is horizontally disposed therebetween. It should be notedhowever that the body 140 is not limited to be horizontally disposed andmay be disposed at an incline in this embodiment.

[0079] Extension Arm 100

[0080] In addition to improvements in manufacturing and assembly, thepresent invention also offers a functional interchangeability which isnot present in the prior art. For instance, several forearm extensions110 and/or extension arms 100 can be connected end-to-end to provideadditional extension length or additional adjustability.

[0081] A dual purpose of flat-screen devices is to minimize the amountof space which they occupy while simultaneously being aestheticallypleasing to the eye. Thus, it is desirable that an extension arm for aflat-screen device be able to be mounted substantially flat to itsmounting surface while hiding the extension arm behind it. The presentinvention permits a flat-screen device which is mounted to a wall to beflattened against the wall while hiding the extension arm 100 within theshadow of the device.

[0082] The prior art extension arms 10 did not allow this functionality.Referring to FIG. 1, if a wall is defined by the plane of the page, itcan be seen that a device inserted into the hole 26 may be substantiallyflattened against the wall when the upper and the lower channels 14, 16and the forearm extension 20 are flush against the wall. A flat-screencomputer monitor, which is typically about 15 inches wide, will hidefrom view the forearm extension 20, but may leave exposed theparallelogram formed by the first end cap 12, the upper channel 14, thelower channel 16 and the second end cap 18. In order to hide theparallelogram, the forearm extension 20 needs to be rotated about theforearm extension pin 92 toward the first end cap 12. However, the upperand the lower channels 14, 16 and the first end cap 12 will prevent theforearm extension 20 from being flush against the wall in thisconfiguration. Thus, it is clear that the prior art extension arms 10could only provide the ability to mount a device˜flush to the wall orthe ability to mount a device so as to hide the forearm extension 20,but not both.

[0083] By contrast, the upper and the lower channels 104, 106 of thepresent invention do not interfere with the rotation of the forearmextension 110. That is, the forearm extension 110 may be folded into aposition which is directly above the upper and the lower channels 104,106. As a result, the mounted device is flush to the mounting surfaceand substantially hides the parallelogram, formed by the first and thesecond end caps 102, 108 and the upper and the lower channels 104, 106,as well as the forearm extension 110 from view. Thus, the aestheticappeal of the extension arm 100 is increased and the space occupied bythe extension arm 100 and the device is minimized.

[0084] While only certain features of the invention have beenillustrated and described herein, many modifications, substitutions,changes or equivalents will now occur to those skilled in the art. It istherefore, to be understood that the appended claims are intended tocover all such modifications and changes that fall within the truespirit of the invention.

1. An upper channel for use in an extension arm that adjustably mounts a device to a support mount, said upper channel comprising a U-shaped body having first and second ends, said body including a pair of spaced apart sidewalls and a bottom wall, a first roller at a first end of said body and a second roller at a second end of said body, said first roller including a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of another portion of said first roller from said bottom wall.
 2. The upper channel of claim 1, wherein said body includes a boss having a threaded hole formed therein extending from said bottom wall between said sidewalls adjacent one end of said body.
 3. The upper channel of claim 2, wherein said boss including said threaded hole is integrally cast with said body and said rollers.
 4. The upper channel of claim 2, further comprising a ball stud threadedly mounted to said threaded hole.
 5. The upper channel of claim 4, further comprising a gas spring rotatably attached to said ball stud.
 6. The upper channel of claim 1, wherein each of said rollers have holes located at a respective axial centerline.
 7. The upper channel of claim 1, wherein said second roller includes a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of another portion of said second roller from said bottom wall.
 8. A lower channel for use in an extension arm that adjustably mounts a device to a support mount, said lower channel comprising a U-shaped body having first and second ends, said body including a pair of spaced apart sidewalls and a bottom wall, a first roller at a first end of said body and a second roller at a second end of said body, said first roller including a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of the remaining portion of said first roller from said bottom wall.
 9. The lower channel of claim 8, wherein said bottom wall of said body has a cable channel aperture formed therein.
 10. The lower channel of claim 9, wherein said cable channel aperture runs along a longitudinal centerline of said body.
 11. The lower channel of claim 9, wherein said cable channel aperture has two opposite edges that are parallel to a longitudinal centerline of said body.
 12. The lower channel of claim 9, wherein said cable channel aperture has two opposite ends, and at least one of the ends is rounded.
 13. The lower channel of claim 9, further comprising a cover that is removably attachable to said cable channel aperture.
 14. The lower channel of claim 9, wherein each of said rollers have holes located at a respective axial centerline.
 15. The lower channel of claim 9, wherein said second roller includes a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of the remaining portion of said second roller from said bottom wall.
 16. The combination of an upper channel and a lower channel for use in an extension arm that adjustably mounts a device to a supporting mount, said combination comprising an upper channel including a U-shaped upper body having first and second ends, said upper body including a pair of spaced apart sidewalls and a bottom wall, a first roller at a first end of said upper body and a second roller at a second end of said upper body, said first roller including a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of the remaining portion of said first roller from said bottom wall; and a lower channel including a U-shaped lower body having first and second ends, said lower body including a pair of spaced apart sidewalls and a bottom wall, a third roller at a first end of said lower body and a fourth roller at a second end of said body, said third roller including a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less to the height of the remaining portion of said third roller from said bottom wall, wherein said upper and lower body and said respective rollers are integrally cast.
 17. The combination of claim 16, wherein said upper body includes a boss having a threaded hole formed therein extending from said bottom wall between said sidewalls adjacent one end of said upper body.
 18. The combination of claim 17, wherein said boss including said threaded hole is integrally cast with said upper body and said first and second rollers.
 19. The combination of claim 17, further comprising a ball stud threadedly mounted to said threaded hole.
 20. The combination of claim 19, further comprising a gas spring rotatably attached to said ball stud.
 21. The combination of claim 16, wherein each of said rollers have holes located at a respective axial centerline.
 22. The combination of claim 16, wherein said second roller includes a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of the remaining portion of said second roller from said bottom wall.
 23. The combination of claim 22, wherein said fourth roller includes a pair of spaced apart roller walls extending between said sidewalls from said bottom wall, the height of said roller walls from said bottom wall being less than the height of the remaining portion of said fourth roller from said bottom wall.
 24. The combination of claim 16, wherein said bottom wall of said lower body has a cable channel aperture formed therein.
 25. The combination of claim 24, wherein said cable channel aperture runs along a longitudinal centerline of said lower body.
 26. The combination of claim 24, wherein said cable channel aperture has two opposite edges that are parallel to a longitudinal centerline of said lower body.
 27. The combination of claim 24, wherein said cable channel aperture has two opposite ends, and at least one of the ends is rounded.
 28. The combination of claim 24, further comprising a cover that is removably attachable to said cable channel aperture.
 29. The combination of claim 16, wherein said upper and lower channels have common opposite ends that are pivotably coupled to a respective first and second end cap 